This invention relates to metal plank grating of the type used in the construction of flooring and subflooring and particularly in mezzanine decks that are erected in warehouses and other buildings.
The utilization of storage space in warehouses and similar buildings can often be made more effective by constructing a mezzanine level deck at a location intermediate the floor and ceiling of the building. The mezzanine provides added floor space at a convenient location that formerly served only as vacant overhead space. The mezzanine provides expansion space without the need to incur the high costs of new building construction.
The mezzanine structure is typically supported by horizontal beams that extend between upright support columns standing on the warehouse floor. Decking is installed on the horizontal beams to form the mezzanine floor. Connected metal planks, which can be either solid surfaces or gratings, are most often used to form the decking. Assembly of the decking normally involves the application of nuts and bolts, crimping of overlapped flanges or similar mechanical fasteners that require tools and the installation costs are relatively high due to the need to connect the planks together. Other problems with conventional plank grating is that the strength is now always sufficient to accommodate the heavy loads that can be applied to the mezzanine deck or to the conventional decks easily applicable for wheel use.
The present invention is directed to an improved plank grating assembly. It is the principal object of the invention to provide a plank grating arrangement which can be quickly and easily assembled, without the need for tools or mechanical fasteners, and which exhibits the strength required by accepted design criteria. Other objects of the invention include the provision of a plank grating assembly which is economical to manufacture, which readily accommodates wheeled goods on the deck surface, and which is constructed to utilize a variable number of cross braces so that different load capacities and concentrated loads can be handled. It is another important object of the invention to provide a plank grating assembly in which the loads are uniformly distributed and effectively transmitted to the main support beams.
In accordance with the invention, the decking is formed by longitudinal planks which are connected with one another and supported by cross braces each having the shape of an inverted V. The cross braces are slotted on both ends and are slipped through openings formed in side flanges of the longitudinal planks. The braces can be rotated into an assembled position in which they lock the flanges of adjacent planks together in order to rigidly connect the planks side by side to form a continuous deck surface. The braces are located immediately beneath the deck surface in order to receive and transmit the loads applied to the deck. The load bearing braces not only transmit loads from the planks to the support beams in an efficient and uniform manner, but they also rigidly connect adjacent planks without using male or female type flanges, without the need to install nuts and bolts or other special fasteners and without the need for crimping tools or other assembly equipment.